More than enough I'm sure but it depends on how many plants are stuffed into a space. If it's packed with plants then either a lot of airflow or CO2 supplementation is needed. With lots of plants the RH will quickly climb and the exhaust fan will be triggered so the airflow problem is solved for that. If only a couple of plants then they aren't going to use up the CO2 so fast so there is less need for as much airflow.
In my instance all the air going into my grow room comes from the greater area of the underground bunker the room is in and stays cool all year round. The highest it gets is maybe 65F tho the last couple summers has only hit 63. Can get down to almost freezing in the winter but usually hovers around 40F. Until recently I was using a 400W CMH light and it didn't warm up the room enough to trip the fan but I wasn't trying to get fast growth out of the two plants in there so no matter. Now there's a 600W MH and the fan kicks in every now and then but I've raised the thermostat to let it get up to about 85 in there so I can burn my alcohol lamp and feed them lots of extra CO2. I just put them in 7gal pots and set up a ScroG screen in preparation for flowering and need to stuff some more but smaller plants in there with them. Going to be a bit crowded but can use the light mover to make sure everybody gets enough light or switch up to 1000W SHPS.
